Newtonian Laws: First, Second, and Third

593 words | 2 page(s)

The three laws of motion were devised in the year 1686 by Sir Isaac Newton. This means that over three-hundred years ago the laws which explain our modern world were understood. Newton developed these laws when he was forty-three years old. He wrote an important piece in scientific literature, Principia Mathematica Philosophiae Naturalis, in which he presented his three laws of motion. Newton’s laws of physics are some of the most well-known laws of physics. The story of the apple falling from the tree is often told story that has become a legend of the laws of motion. The story goes that Isaac Newton had a realization after he saw an apple fall from the tree. He reasoned that the same force that the apple fell from is what regulates the motion of everything in the universe, i.e. gravity. Therefore, Newton devised three primary laws of motion, and the law of gravity. This paper discusses the three laws of motion.

First law. Newton’s first law of motion is that an object at rest will stay at rest, and an object in motion stays in motion. One of the ways that this law is interpreted is a law of inertia-basically however an object is, or is not, moving will remain the same unless interrupted by an outside force. This is a law that has helped scientists understand the way that an object keeps a constant velocity, and that it is only when there is some sort of external force that the velocity changes. Things stay the same unless something changes them.

Second law. The second law takes off from where the first law leaves off. The external force that the first law describes is explained in the second law as the force is equal to the change in momentum. There is a calculus equation which comes from this law: Force is equal to the change in momentum. Therefore, an object with a constant mass, the force is the mass times the acceleration of the change. It is expressed as F= m * a. What this means is that the way that a velocity changes will depend upon the force of the external object and the mass, or size, of the object that is being impacted. The equation works both ways and a change in velocity will depend on the mass a constant force. The force of the change to an object’s constant motion is equal to the change in momentum.

Third law. The third law might be one of the most well known of the three laws. The law is that for every action in the natural world, there is an equal and an opposite reaction to the action. Therefore, this means that whatever type of force is applied to an object, the object will receive that amount of force in return. The third law of motion is the law which explains the phenomenon of an airplane’s flight. There is force from the lifting of the wings and the power of the engines which gain the same resistance. Things exert the same amount of force on each other in a positive and negative manner.

Conclusion
Although these laws of motion are over three-hundred years old, they have been unchanged since Newton’s first presentation. He understood the physics of an airplane long before an airplane was ever considered. It is because of these laws that physics has been able to progress. These three laws of motion are core foundational laws of physics and science; they are applicable to all objects, no matter how small or large.